Cutting device

ABSTRACT

A cutting device provided with a needle-shaped cutting member which is at its free end provided with at least one cutting edge at an angle with the longitudinal axis and coupled to a driving mechanism which is constructed in such a way that during operation the cutting edge is periodically raised to above the material and can be rotated at the same time through an angle.

United States Patent 1 Glastra [451 June 26, 1973 CUTTING DEVICE [75] Inventor: Hendrik Glastra,Enschede,

Netherlands [73] Assignee: N.V. Maatschappij Voor lndustriele Research en Ontwikkeling, Enschede, Netherlands 22 Filed: Apr. 8, 1971 21 Appl. 190.; 132,291

52 vs. C] 83/556, 83/170, 83/561, 83/747, 83/925 cc 51 Int. Cl 826d 5/14 [58] Field of Search 83/556,925 cc, 561, 83/170, 747

[56] References Cited UNITED STATES PATENTS 3,477,322 11/1969 Gerber et a1 83/556 X 2,073,219 3/1937 Moulton 83/556 X Primary Examiner.1. M. Meister Attorney-Woodhams, Blanchard and Flynn [57] ABSTRACT A cutting device provided with a needle-shaped cutting member which is at its free end provided with at least one cutting edge at an angle with the longitudinal axis and coupled to a driving mechanism which is constructed in such a way that during operation the cutting edge is periodicallyraised to above the material and can be rotated at the same time through an angle.

4 Claims, 4 Drawing Figures Patented June 26, 1973 3,741,062

2 Sheets eet 1 I ATTO NEY Patented June 26, 1973 VIA 2 Sheets-Sheet 2 INVENTOR HF P m v L/nr/m CUTTING DEVICE BACKGROUND OF THE INVENTION My invention relates to a cutting device for cutting up material and provided with an oblong cutting member which is clamped at one end and can be moved up and down in its longitudinal direction by means of a driving mechanism.

Such cutting mechanisms are known in many versions and generally comprise a cutting knife, of which the cutting edge is substantially parallel to the longitudinal axis of the knife, while during the cutting operation this cutting edge does not rise above the material to be cut. The action of such a cutting mechanism is therefore substantially the normal cutting, or sawing action.

Such cutting mechanisms have various drawbacks. Owing to its longitudinally extending cutting edge it is necessary. that the blade has a certain minimum dimension in the transverse direction which makes it difficult to make acute angles when following a curved path. Preferably one will want to make the cutting blade as thin as possible, thereby decreasing its rigidity and introducing the risk of undesired lateral movements. If the cutting knife becomes blunt it must be trimmed along the entire, long, cutting edge or be replaced. A considerable drawback of such a cutting mechanism is in the fact that necessarily a certain pressure in the direction of advance must be exerted on the material to be cut whereby, particularly when cutting through one or a few layers, the material tends to ripple up before the knife. It has been attempted to eliminate this drawback by using complicated presser members. A thin knife requires the use of a special holder which has disadvantages (friction between knife and holder, higher temperature) and, when cutting patterns, more waste owing to the necessary distance between two adjacent cuts.

SUMMARY or THE INVENTION It is an object of my invention to provide acutting mechanism of the abovementioned kind without the aforementioned drawbacks and using an' easily produced inexpensive cutting member which can be used to cut without producing thresses.

To that end the cutting member is, according to my invention on its free end provided with at least one cutting edge at an angle with the longitudinal axis, while the driving mechanism is constructed in such a way that during operation the cutting edge is periodically raised to above the material and can be rotated at the same time through an angle.

My invention is in fact based on the understanding that the so far used cutting or sawing treatment can advantageously be replaced by an operation which in fact is a chopping treatment with the effect that the material is as it were chopped by the sharp edge(s) at the lower end of the cutting member when same moves downwardly.

The angular displacement of the needle can be coupled to the direction in which the material should be cut, or may be arbitrary. In the first case the needle is guided in such a way that it can rotate around its longitudinal axis while it is connected with a coupling piece which cooperates with an adjusting member, the position of which determines the angular position of the cutting edge when the needle is moving downwardly.

The driving mechanism comprises a continuously rotated eccentric which is coupled to one end of a driving rod the other end of which drives a sliding piece guided in a suitable guiding means and in which is freely rotatably supported a shaft. One end of the shaft carries a chuck for the cutting member, and the other end is connected to a flat oblong coupling, piece. The free end of the coupling piece fits into a coupling bush having an elongated, axial, recess with tapering walls ending into a slit. The coupling bush is in axial alignment with the shaft, and is guided in the housing of the driving mechanism in such a way that it can be rotated so that its angular position, and as a consequence the angular position of the needle, when moving downwardly, are adjustable by means of an external control.

In another embodiment of my invention in which the needle is subjected to an arbitrary angular displacement the driving mechanism comprises a continuously rotating eccentric which is by its one end coupled to the one end of a driving rod, of which the other end drives a sliding piece supported in suitable guide means. This sliding piece supports a free rotating shaft of which the one end carries a chuck for the cutting member. The other end of the sliding member tapers so as to fit with friction into a corresponding cavity of a free rotating driving wheel which is coaxially aligned with the shaft and positioned in such a way with respect to the eccentric and the driving rod that the latter, when being in its upper most position, in which the conical end of the shaft is in contact with the cavity, takes along during its movement the outer circumference of the wheel through an angle.

SUMMARY OF THE DRAWINGS FIG. 1 shows a longitudinal section through a first embodiment of the driving mechanism for the cutting member;

FIG. 2 shows a perspective view of such a mechanism;'and

FIG. 3 shows partially a sectional view partially a-sid elevation of a second embodiment of the driving mechanism; and v v FIG. 4 shows an end view of the bush as used in this mechanism.

DESCRIPTION OF PREFERRED EMBODIMENTS The cutting mechanism as shown in the figures corisists substantially of a housing 1 containing the driving and supporting members, and the cutting member driven thereby. The cutting mechanism can e.g. be used into a cutting machine for cutting up sheet or fibrous material, particularly a number of textile layers lying on each other.

The cutting member 2 has an elongated cylindrical shape and the shown embodiment has at its underside a single cutting edge 3 which is perpendicular to the longitudinal axis of the cutting member 2. This short cutting edge can, if desired be trimmed simply and fast.

The cutting member 2 is with its other end gripped in a chuck 4 carried by a shaft 5. This shaft can, by means of bearings, (not shown)' freely rotate in a sliding piece 6 and has at itsother end a tapering tip 7. The sliding piece 6 is slidably guided in a longitudinal direction between two guide blocks 8 (viz. FIG. 2). These guide blocks 8 lie between the bottom part 9 and the upper piece 10 of the housing 1 which'has a substantially U-profiled longitudinal section. Each guide block is in a thermally conductive connection with a number of cooling ribs 11, so that, when the sliding piece 6 moves fast in the guide blocks 8, the temperature cannot rise too much. Furthermore there are provisions for lubrication (not shown).

Besides the up and down movement of the cutting member during operation, a rotation thereof around its axis must also be possible. The up and down movement is brought about by means of an eccentric-crank-shaft combination which is driven in rotation. A circular recess is provided in the back wall 12 of the housing in which is accommodated an eccentric 13 mounted on the shaft 14 supported in the bearing 15, the latter accommodated in the stub 16, while at the end of the shaft the drive, in this case the driving pulley 17, is secured.

The eccentric 13 carries the shaft 18 on which is supported the end 19 of the connecting rod 20. The other end 21 of the connecting rod 20 carries the shaft 22 which is fixed to the sliding piece 6.

1 The up and down movement of the cutting member 2 is obtained by means of the eccentric 13 and the driving rod 20. The driving wheel 23 has a shaft 24 journalled in the bearing 25 in the upper part 10 of the housing 1 and imparts a rotary movement to the cutting member. The driving wheel 23 has a cylindrical part 26 with a conical cavity 27 of which the shape corresponds with same of the part 7 of the shaft 5. The part 26 is either of material with a high coefficient of friction, e.g. rubber, or the inner wall of the cavity 27 is lined with such a material. When the tip 7 lies within the cavity 27 and the wheel 23 rotates, the tip 7 is driven by it. The wheel 23, the eccentric 13, and the end '19 of the driving rod are positioned in such a way with respect to each other that in the uppermost position of the driving rod 20 the upper edge of the head'19 is during the upper part of its path in contact with the outer edge 28 of the wheel 23 (made for example of Vulcolan) and turns this wheel through an angle. Simultaneously, however, the tip 7 of the shaft 5 lies within the cavity 27 and is in contact with the inner wall thereof so that also the shaft 5 is turned through an angle.

FIG. 3 shows a section through a driving mechanism generally like that of FIG. 1 but constructed to positively control the angular position of the cutting needle when same is moving down. In FIG. 3 the parts corresponding to those of FIG. 1 are designated with identical numeral references.

The end 5' of the shaft 5 carries in this embodiment a flat elongated coupling piece 29 which cooperates with a coupling bush 30. This bush 30 is guided in the guide bush 31 in the upper end of the housing and the angular position thereof can be adjusted at will, e.g. by means of an adjusting mechanism (not shown) acting upon a gear wheel 32 connected with the coupling piece. I

As is represented in FIG. 3 the bush 30 has a recess 32 which from the lower end of the bush, where the recess is entirely circular, tapers to a slit-shaped end 33. As a result the angular position of the coupling piece 29 and of the shaft 5 and the cutting needle 2 in the uppermost position of these parts is determined by the angular position of the slit 33 with respect to the housing. When therefore during the up and down movement of the cutting member 2 the angular position of the bush 33 is changed, e.g. is controlled in accordance with the direction of cutting to be followed, then during each upwardly directed movement of the cutting member the latter will always be brought to the (new) position of the coupling piece. In this way the cutting edge of the cutting member is always directed in the direction in which the cut should be made.

Without further arrangements it might be possible to rotate the bush 30, when the machine is at rest and the coupling piece 29 in its lowermost position, into a position in which the slit 33 is perpendicular to the narrow end of the coupling piece 29. Then there is the risk of the coupling piece being damaged when it moves upwardly. To avoid this from happening the bush 30 is partly closed at its lower end by two segment-shaped small plates 34, 35 (see FIG. 5) which, when in the position of rest the bush 30 is turned through more than 45 in one direction or the other, take the coupling piece 29 along and in this way prevent the above mentioned situation.

What I claim is:

1. In a cutting device for sheetlike material, said cutting device having an elongated cutting member provided with a cutting edge on one end thereof, and a driving mechanism coupled to the other end of said cutting member for reciprocating said cutting member in its longitudinal direction between a position in which the cutting edge penetrates the material and a position in which the cutting edge is free from said material, said driving mechanism comprising a rotatable eccentric, a driving rod having one end thereof coupled to said eccentric whereby said driving rod is driven by said eccentric, elongated guide means, slide means slidably mounted on and guided by said guide means for slidable movement longitudinally thereof, said slide means being coupled to the other end of said driving rod whereby said slide means is reciprocated on said guide means in response to rotation of said eccentric, shaft means freely rotatably supported on said slide means, chuck means mounted on one end of said shaft means for engaging said other end of said cutting member, and control means operatively interconnected to the other end of said shaft means for varying the angular position thereof relative to its longitudinal axis for varying the angular position of the cutting edge relative tosaid axis.

2. A device according to claim 1, wherein said control means includes a rotatable control member substantially coaxially aligned with and disposed adjacent said other end of said shaft means, said control member having a recess in the end thereof disposed opposite said shaft means for receiving therein the adjacent end of said shaft means.

3. A device according to claim 1, wherein said control means includes a rotatable control member disposed in axial alignment with said shaft means, said control member being disposed opposite said other end of said shaft means, said control member having an elongated axial recess with tapering walls ending in a slit, and said other end of said shaft means including a flat elongated coupling member extending along said axis and having a free end thereof disposed within said axial recess, and a control element interconnected to said control member for rotating same about said axis to vary the angular position of said control member and as a consequence vary the angular position of the cutting member when same is being moved toward a position in which it penetrates the material.

4. A device according to claim 1, wherein the control means includes a driving rotatable control member dismanner that when the shaft means is adjacent said second position said tapered end of said coupling member is engaged with the wall defining said cavity and said driving rod and said eccentric engage said control member and cause angular displacement thereof for causing a corresponding angular displacement of said cutting edge. 

1. In a cutting device for sheetlike material, said cutting device having an elongated cutting member provided with a cutting edge on one end thereof, and a driving mechanism coupled to the other end of said cutting member for reciprocating said cutting member in its longitudinal direction between a position in which the cutting edge penetrates the material and a position in which the cutting edge is free from said material, said driving mechanism comprising a rotatable eccentric, a driving rod having one end thereof coupled to said eccentric whereby said driving rod is driven by said eccentric, elongated guide means, slide means slidably mounted on and guided by said guide means for slidable movement longitudinally thereof, said slide means being coupled to the other end of said driving rod whereby said slide means is reciprocated on said guide means in response to rotation of said eccentric, shaft means freely rotatably supported on said slide means, chuck means mounted on one end of said shaft means for engaging said other end of said cutting member, and control means operatively interconnected to the other end of said shaft means for varying the angular position thereof relative to its longitudinal axis for varying the angular position of the cutting edge relative to said axis.
 2. A device according to claim 1, wherein said control means includes a rotatable control member substantially coaxially aligned with and disposed adjacent said other end of said shaft means, said control member having a recess in the end thereof disposed opposite said shaft means for receiving therein the adjacent end of said shaft means.
 3. A device according to claim 1, wherein said control means includes a rotatable control member disposed in axial alignment with said shaft means, said control member being disposed opposite said other end of said shaft means, said control member having an elongated axial recess with tapering walls ending in a slit, and said other end of said shaft means including a flat elongated coupling member extending along said axis and having a free end thereof disposed within said axial recess, and a control element interconnected to said control member for rotating same about said axis to vary the angular position of said control member and as a consequence vary the angular position of the cutting member when same is being moved toward a position in which it penetrates the material.
 4. A device according to claim 1, wherein the control means includes a driving rotatable control member disposed opposite and in substantial axial alignment with said other end of said shaft means, said control member having a tapered concentric cavity extending inwardly from the end thereof, and said other end of said shaft means including a coupling member having a tapered free end which engages with friction within the cavity formed in said control member, said control member and said coupling member being positioned with respect to said eccentric and said driving rod in such a manner that when the shaft means is adjacent said second position said tapered end of said coupling member is engaged with the wall defining said cavity and said driving rod and said eccentric engage said control member and cause angular displacement thereof for causing a corresponding angular displacement of said cutting edge. 